[ https://issues.apache.org/jira/browse/CASSANDRA-16072?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Benjamin Lerer updated CASSANDRA-16072: --------------------------------------- Complexity: (was: Low Hanging Fruit) > Reduce thread contention in CommitLogSegment and HintsBuffer by rewriting CAS > loops to atomic adds > -------------------------------------------------------------------------------------------------- > > Key: CASSANDRA-16072 > URL: https://issues.apache.org/jira/browse/CASSANDRA-16072 > Project: Cassandra > Issue Type: Improvement > Components: Consistency/Hints, Local/Commit Log > Reporter: Michael Semb Wever > Assignee: Michael Semb Wever > Priority: Normal > Fix For: 3.11.x, 4.0.x > > > Follow up to CASSANDRA-15922 > Both CommitLogSegment and HintsBuffer use AtomicIntegers for the current > offset when allocating. Like in CASSANDRA\-15922 the loops on > {{.compareAndSet(..)}} can be replaced with atomic adds using the {{. > getAndAdd(..)}} method. > In highly contended environments the CAS failures can be high, starving > writes in a running Cassandra node. On the same cluster CASSANDRA\-15922 was > found, after CASSANDRA\-15922's fix was deployed, there was still problems > around commit log flushing and hints. No flamegraph was collected that > demonstrated the thread contention as clearly as was found in > CASSANDRA\-15922, but the performance fix proposed here hopefully is obvious > enough. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org